Apparatus for conveying gases or liquids



July 1, 1958 P. SCHAURTE APPARATUS FOR CONVEYING GASES OR LIQUIDS FiledNov. 15, 1954 3 Sheets-Sheet 1 July 1, 1958 sc 2,841,091

APPARATUS FOR CONVEYING GASES 0R LIQUIDS Filed Nov. 15. 1954 sSheets-Sheet 2 Z'X /K m d// July 1, 1958 P. SCHAURTE APPARATU FORCONVEYING GASES OR LIQUIDS Filed Nov. 15, 1954 5 Sheets-Sheet 3 Fly. 9

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mcimu s .Q-h-M United States Patent "'ice APPARATUS FOR CONVEYING GASES0R LIQUIDS Paul Schaurte, Schaan-Sax, Liechtenstein Application November15, 1954, Serial No. 468,946

Claims priority, application Germany November 16', 1953 16 Claims. c1.10s 149 The present invention relates to an apparatus for con veyinggases or liquids. I

More particularly, the invention relates to conveyors, pumps, flowmeters or the like of the type in which a liquid or gaseous medium isbeing moved Within an annular resilient channel or the like which isprogressively compressed by one or more elements which are being movedabout a central axis so as to roll along the surface of the annularchannel, thereby pushing the respective medium within the channel fromits inlet toward its outlet openings which are separated from each otherby a suitable wall or the like, the channel portions immediately afterbeing released by the compression elements spring ing back to theiroriginal cross-sectional area for admitting another charge of medium tobe pushed along by the rolling element as it comes around again to theinlet side of the annular resilient channel.

Various designs of such pumps have previously been made including thetype in which the annular resilient channel overlies an annular grooveinto which the channel is depressed by one or more elements which aremoved along the upper surface of the channel, thereby progressivelydepressing the channel into the groove. In some of these designspressure elements were moved along the resilient channel so as to pressit only upon the central part of the groove, leaving the side wallssubstantially untouched by the resilient channel, while in other designsthe pressure element together with the resilient channel were fillingthe groove at that particular place entirely. A

Although pumps of this general type have the great advantage over othertypes of pumps of not requiring any control means such as valves,slides, or the like, and of being of simple construction, not requiringa very high degree of accuracy of manufacture, they have not provedsuccessful in actual practice primarily for the reason that in all thedesigns known the circulatingpressure elements either do not close ofithe resilient channel entirely, thus permitting a portion of therespective medium to flow back and resulting in an inefficientoperation, or the pressure elements exert a squeezing or mashing actionupon the resilient channel and tend to drag along the resilient materialin the direction of their movement, thus resulting in excessive wearupon the resilient material. The

amount of service required by pumps of these types, if they were tooperate at all efficiently insofar as their actual pumping action or thequantity of medium conveyed thereby is concerned, was so large due tothe necessary frequent changes of the'resilient conveying means that thecost and trouble of such service far outweighed their advantages.

It has now been found according to the invention that the failure of theprior designs of pumps of this general type are due primarily to thefact that their pressure elements were mounted rigidly on the rotatingdrive shaft, thus exerting a mashing, squeezing, or tearing action uponthe resilient channel, rather than aresilient rolling action 2,841,091latented July 1, 1958 which automatically adapts itself to theyieldingness of the channel material and the pressure in such channel.

According to another type of pump previously known, the resilientchannel of the designs as described above was replaced by a resilientdiaphragm which was spaced a certain distance from an inner surface ofthe pump housing so as to form an intermediate channel which connectedthe inlet and outlet openings of the pump. This channel was thenpartitioned progressively at one point after another by a series oftappetsor rams pressing the resilient diaphragm toward the inner surfaceof the housing and thus successively closing the channel or reducing thecross-sectional area theerof, or moving the partition thus formed alongthe housing surface toward the outlet. According'to a preferredembodiment of this prior design, the housing was made of annular-shapewithin which the rams or tappets were provided about a central revolvingshaft and successively actuated in a radial direction by a cam on suchshaft lifting the tappets against the resilient diaphragm to press thesame progressively toward the cylindrical inner surface of the pumphousing. In still another embodiment of such prior design, the channelformed intermediate the nonresilient surface and the resilient annulardiaphragm was located within a plane vertically to the drive shaft whichexerted a pressure upon the diaphragm by means of rollers mounted on anaxis extending vertically to, and positively secured to, the driveshaft, thus rolling such rollers along the surface of the diaphragmabout such central driving axis and pressing the points contacted by therollers toward the nonresilient surface. e v 7 Either one of these pumpdesigns in which the conveying channel was formed intermediate anonresilient surface and. a resilient diaphragm had the disadvantagethat the pump could work only if the medium to be conveyed therebyentered the pump under pressure, and that such pressure within theconveying channel had to be sufficient to return the tappets or ramsafter pressing upon the diaphragm, to their original position. Thesedesigns had the further considerable disadvantage that they only alloweda partial compression of the conveying channel, thus being veryinefiicient in their operation, and that the movement of the tappets wasdirected at substantially a right angle relative to the direction offlow, so that the pressure of the medium itself tended to jam thetappets and prevented them from returning to their original position.

It is the object of the present invention to devise an apparatus forconveying gaseous or liquid media which is adapted to be used either asa pump, as a flow meter, or the like, and which in some respects issimilar to the prior pump designs as above described insofar as itoperates'according to the same general principle, but overcomes all thedisadvantages of such prior deisgns, thus rendering it highly efiicientand reliable in operation, requiring little, if any, service or repair,and being adapted to be produced at a low cost.

The essential features of the invention for attaining such object residein theprovision of a conveying channel of a particular cross-sectionalcurvature, the generatrix of which essentially consists of a centralcircular are which terminates toward both ends into an oppositecurvature, and in the cooperation with such groove or channel of aresilient diaphragm overlying such groove or channel and being depressedtherein by one or more spherical balls which, while being rolled alongthe surface of the diaphragm, are being held under a resilient pressurein accordance with the resiliency of the dia: phragm and the pressure ofthe respective medium to be conveyed.

; An important advantage of the invention resides in the fact that,through the cooperation of the resilient elements acting upon the balls,the particular manner of guiding these balls so as to roll along thesurface of the diaphragm, and the particular curved shape and thedimensions of the groove or channel, the balls may act upon thediaphragm so as to close off the channel entirely at the particularpoint where the balls exert their pressure upon the diaphragm without,however, thereby causing anyconsiderable friction between the balls andthe resilient material of the channel which might be harmful thereto. a

Another feature of the invention resides in the provision of tapered.rollers intermediate adjacent balls for the control of higher pressuresin the conveying channel and for preventing'the resilient diaphragm frombeing forced outwardly by such high pressure.

Further objects, features, and advantages of the present invention willbe apparent from the following detailed description and the accompanyingdrawings, in which 'Fig. 1 shows a cross section through an apparatusaccording to the present invention, in which the diaphragm is acted uponby three balls;

Fig. 2 is a cross sectiontaken along line A--B of Fig. 1;

Fig. 3 is a cross section taken along line CD of Fig. 2;

Fig. 4 is a fractional section taken at a right angle to Fig. 2 alongline E-F as seen from the point G in Fig. 2;

Fig. 5 is a partial section taken along line H--I of Fig. 2 showinganother embodiment of the invention in which the diaphragm is securedrelative to the housing;

Fig. 6 is a top view in reduced size of the guide means which aredesigned to take up the centrifugal forces of the balls;

Fig. 7 is a top view in reduced size of a diaphragm according to theinvention;

Fig. 8 shows a cross section through a tapered roller, the central partof which is ball-shaped;

Fig. 9 shows a cross section through an apparatus according to theinvention, in which the diaphragm is acted upon by balls and taperedrollers; while Fig. 10 is a top view of the apparatus shown in Fig. 9prior to the installation of the resilient guiding means for the ballsand tapered rollers and the housing cover.

Referring to the drawings, the housing 1 has provided therein an annulargroove 2, the generatrix of which substantially consists of a centralcircular arc terminating into two curved portions so that the commontangent determined by the points of connection with the circular arcappears as a tangent through the point of inflection. The radius of thecentral arc is made equal to, or smaller than the sum of the radius ofthe spherical body 3 and the thickness of the diaphragm 4 which issuperposed upon the groove and is capable of filling out the area formedby the groove. It is not required, according to the invention, that thegeneratrix consisting of three curved sections has an axis of symmetry.A groove designed as thus described has the advantage that thecrosssectional area thereof may be enlarged without requiring thecontact surface between the balls 3 and the annular diaphragm 4 also tobe enlarged. Frictional losses and the wear upon the diaphragm will thusbe reduced. The stretch of the diaphragm in a radial direction will thusbe the same regardless of the cross sectionthereof, that is, equal tothe angle of pressure times 1r times the sum of the radius of the ballplus the thickness of the diaphragm plus the radius of the outer arc ofthe generatrix.

Such a design of the groove coupled with the use of balls permits theresilient material when acted upon by the balls to be pressed evenly andfully upon the inner surfaces of the groove, since the parts on bothsides of the central arc of the generatrix of the groove are curved inthe opposite direction. T

In the embodiment of the invention shown in Figs. 1 and 2, the balls 3are being retained within a cage 5 form- 4 ing a single element, andthey are acted upon by a disk 6 which is positively connected with therotating shaft 7, for example, by a driving pin 8 or the like, whichengages in slots 9 in the disk 6. Such arrangement allows the balls 3and their cage 5 to rotate at half the angular velocity of the shaft 7.Disk 6 is acted upon by one or more resilient means, such as a spring 10which at one end presses upon the disk 6 and at the other end upon adisk 11. For preventing the balls 3 from slipping relative to the disk6, it is advisable to cover the side of the disk 6 facing the bodies 3with a material similar to that of the diaphragm 4. Disk 11 is rotatablysupported on the housing cover 12 by means of an axial bearing 13, andshaft 7 by a radial bearing 14 in the housing 1 and another radialbearing 15 in the housing cover 12. Bearing 14 is being protected andsecured in place by a cap 16, and bearing 15 by a cap 16. Cover 12 andhousing 1 are secured to each other by suitable means, such as bolts 17.Diaphragm 4 is fixed in place relative to the housing 1 by two rings 18and 19, for

- example, by means of screws 20. Bolts 17 may also act as means forsecuring the diaphragm 4 relative to the housing 1. Diaphragm 4 carriesa downwardly projecting lug 21 which extends in a radial direction andvertically to the diaphragm body, forming a part thereof. At the pointwhere the lug 21 is connected to the body of the diaphragm 4, the latteris shaped so as to form a troughlike depression 22 which, as seen in aradial cross section, has the same generatrix which the diaphragmassumes through the pressure of the rolling bodies 3 at those pointsacted upon by them. The projecting lug 21 acts as a partition toseparate the inlet and outlet sides of the troughlike groove. If theballs 3 are being rotated so as to move in the direction of the arrow23, the gases or liquids to be conveyed enter the apparatus through theinlet 24 and emerge therefrom through the outlet 25 which communicatewith channels 26 and 27, respectively, which terminate into thetroughlike groove 2. Threaded sockets 28 and 29 may be provided at theouter ends of channels 24 and 25 into which suitable conduits, such aspipes, hoses, or the like may be screwed for passing the gases orliquids into and from the groove or channel 2 in the housing 1. When theshaft 7 is being rotated, the balls 3, since they are being resilientlyforced by the rotating disk 6 against the annular diaphragm 4, rollabout their horizontal axis 30 in the direction of the arrow 23 at anangular velocity equal to half the speed of rotation of shaft 7.

Thus, since three balls 3 are provided, they are being pressed at threedifferent, equally spaced points against the diaphragm 4 so that thetroughlike groove 2 is being filled out by the diaphragm at these pointsand partitioned to form three intermediate chambers which do notcommunicate either with the inlet 24 or the outlet 25. As a result ofthe rotary movement of the balls 3, the liquid or gaseous mediumcontained in these chambers will be conveyed along'the groove 2 until itemerges from the housing 1 through the outlet channels 25 and 27. At thesame time, additional amounts of such medium are being drawn into thetroughlike groove 2 through the inlet 24, while another intermediatechamber filled with the respective medium is being moved along thegroove.

In order to insure a smooth operation of the apparatus without knocking,compensating slots 31 and 32 may be provided in the bottom of the groove2 at each side of the lug 21 so as to prevent the inlet and outletopenings from being closed entirely by the rolling balls.

If the apparatus is to be used, for example, as a flow meter, thepressure of the respective medium to be measured entering into thegroove 2 itself effects the rotation of the balls 3 and thereby of theshaft 7, which in such a case is to be coupled with a suitable registerof customary design.

The troughlike groove 2 may also be partitioned in a manner ditferentfrom that illustrated in Figs. 1 and 2 by the lug 21. Thus, as showninFig. 5, it may be fully suflicient to draw the diaphragm 4 by means of abolt 33 with a nut 34 into a recessed portion 35 in such a manner that atroughlike groove 22' similar to groove 22 will be formed.

Also, in place of the cage 5 consisting of a single element, a cage 36may be provided, as illustrated in Fig. 6, which is open toward theoutside. In such a case, a ring 37 may be provided which lies within theplane of the rotary axis 30 of the balls 3 and takes up the centrifugalforces occurring therein.

For increasing the resilient strength of the diaphragm 4 especially atthe suction side of the apparatus, an elastic insert 33, as shown inFig. 7, may be provided within the diaphragm 4. Such insert may consist,for example, of an endless wire, several individual wires, or syntheticfibrous material essentially arranged in a radial direction.

By a suitable selection of the appropriate resilient means which actupon the balls 3 it is possible to limit the pressure exerted upon themedium to be conveyed. If the predetermined pressure is being exceeded,the diaphragm will not lie solidly against the wall surface of groove 2so that a liquid layer may slide between the diaphragm 4 and the wall ofgroove 2 and lift the disk 6. Thus, if an excessive pressure shouldoccur, the driving means may be stopped, for example, by the disk 6which is shifted in an axial direction, then actuating suitable controlmeans which, in turn, act upon the respective driving means. In thisconnection it is also advisable to provide suitable means for adjustingthe tension of the resilient means 10 during the operation of theapparatus. V

Since at higher pressures the diaphragm 4 may be resiliently bentupwardly toward the side of the rollers 3, it is advisable, asillustrated in Figs. 9 and 10, to provide substantially tapered rollers39 in a suitable cage between adjacent balls 3, such rollers, on the onehand, acting against the surface of the diaphragm 4, and, on the otherhand, against an annular, bell-shaped member 40.

The bell-shaped member 40 as well as the disk 6 acting upon the balls 3may be positively connected to the shaft 7 by a driving pin or pins 41fitting into slots 42. The bell-shaped member 40, as distinguished fromthe disk6', is, however, unable to shift in the axial direction of shaft7' since it is directly connected to the housing cover 12 through theaxial bearing 43. Disk 6', on the other hand, acts upon the annularmember 40 through resilient means, for example, one or more springs 10'.Disk 6' is being driven by pins 8' which are secured to the member 40and engage into recesses 9' within the peripheral wall of disk 6'.

In the embodiment shown in Figs. 9 and 10, a common cage 44 is providedfor the ball rollers 3 as well as the tapered rollers 39. The diaphragm4 is secured Within the housing 1 in the same manner as in theembodiment shown in Fig. 1. The tapered rollers 39 may also have aspherical central portion 39, as shown in Fig. 8, the diameter D ofwhich is smaller than twice the radius r of the generatrix 45 thereof.Depending upon the number of individual chambers into which thetroughlike groove 2 is partitioned, a smaller or larger number of ballsand tapered rollers may be provided. If the groove 2 is to bepartitioned at only one point, it is advisable to provide three balls 3.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments thereof, it will be understood bythose skilled in the art that various changes and modifications may bemade Without departing from the spirit and scope of the invention asdefined in the appended claims.

Having thus described my invention, what I claim as new is:

1. An apparatus for conveying a gaseous or liquid medium comprising ahousing, a central shaft rotatable within said housing, said housinghaving a substantially level surface therein extending at a right angleto said shaft, an annular groove within said surface coaxially with saidshaft, a resilient diaphragm superposed upon said groove, said grooveand diaphragm together forming an annular channel, an inlet and anoutlet for said medium near each other in said housing and communicatingwith said channel in such a manner that communi cation between saidinlet and said outlet is established through said groove by Way of along arcuate chamber as well as by way of a short arcuate chamber, apartition within said short arcuate chamber of said groove and formingan integral part of said diaphragm so as to close off the communicationbetween said inlet and outlet by way of said short arcuate chamber ofsaid groove, at least one spherical element, means for guiding said element so as to roll along a circular path coinciding with a verticalcylindrical plane passing through the center of said annular groove, asseen in a cross section thereof, pressure means connected with saidshaft so as to rotate therewith and pressing upon said spherical elementand in frictional contact therewith, said annular groove when seen incross section having a central concave portion in the shape of an arc ofa circle having a diameter substantially equal to the diameter of saidspherical element plus the thickness of said diaphragm, and a convexportion at each side of said central portion gradually merging into saidlevel surface in said housing, said spherical element being depressed bysaid pressure means upon said diaphragm, thus pressing said diaphragminto said groove so as to fill out said groove at such particular pointcompletely, whereby when said spherical element rolls along saidcircular path in one direction and simultaneously depresses saiddiaphragm into said groove, it progressively pushes said medium alongsaid channel from the inlet to the outlet thereof.

2. An apparatus for conveying a gaseous or liquid medium compressing ahousing, a central shaft rotatable within said housing, said housinghaving therein a lower portion with an upper substantially level surfaceextending at a right angle to said shaft, an annular groove within saidupper surface coaxially with said shaft, a resilient diaphragm on saidsurface and superposed upon said groove, said groove and diaphragmtogether forming an annular channel, an inlet and an outlet for saidmedium substantially adjacent each other in said housing andcommunicating with said channel in such a manner that communicationbetween said inlet and said outlet is established through said groove byWay of a long arcuate chamber as well as by way of a short arcuatechamber, a partition within said short arcuate chamber of said grooveand forming an integral part of said diaphragm so as to close off thecommunication between said inlet and outletby way of said short arcuatechamber of said groove, at least one spherical element, means forguiding said element so as to roll along a circular path coinciding witha vertical cylindrical plane passing through the center of said annulargroove, as seen in a cross section thereof, and resilient means infrictional contact with said. spherical element, said last means beingpositively connected with said shaft so as to rotate therewith butallowing resilient movement of said spherical element in axial directionof said shaft, said annular groove when seen in cross section having acentral concave portion in the shape of an arc of a circle having adiameter substantially equal to the diameter of said spherical elementplus the thickness of said diaphragm, and a convex portion at each sideof said central portion gradually merging into said level upper surfaceof said lower housing portion, said resilient means pressing saidspherical element upon said diaphragm, and thus said diaphragm into saidgroove so as to fill out said groove at such particular pointcompletely, said spherical element, when rolling along said circularpath in one direction and simultaneously depressing said diaphragm intosaid groove, progressively pushing said medium along said channel fromthe inlet to the outlet thereof.

3. A pump for conveying a gaseous or liquid medium comprising a housing,a central drive shaft rotatable within said housing, said housing havingtherein a lower portion with an upper, substantially level surfaceextending at a right angle to said shaft, an annular groove within saidupper surface coaxially with said shaft, a resilient diaphragm on saidsurface and overlying said groove, said groove and diaphragm togetherforming an annular channel, an inlet and an outlet for said mediumsubstantially adjacent each other in said housing and communicating withsaid channel in such a manner that communication between said inlet andsaid outlet is established through said groove by way of a long arcuatechamber as well as by way of a short arcuate chamber, a partition withinsaid short arcuate chamber of said groove and forming an integral partof said diaphragm so as to close off the communication between saidinlet and outlet by way of said short arcuate chamber of said groove, aplurality of spherical elements in direct contact with the upper surfaceof said diaphragm, means for guiding said elements so as to roll along acircular path coinciding with a vertical cylindrical plane passingthrough the center of said annular groove, as seen in a cross sectionthereof and resilient means in frictional contact with said sphericalelements, said last means comprising an annular disk, said disk beingpositively connected with said shaft so as to rotate therewith butadapted to slide in axial direction of said shaft, and a spring mountedon said drive shaft and acting upon said disk to press the sameresiliently upon said spherical elements and thus said elements uponsaid diaphragm, and said diaphragm into said groove so as to close saidgroove entirely at such points, said groove when seen in cross sectionhaving a concave central portion in the shape of an arc of a circlehaving a diameter substantially equal to the diameter of said sphericalelements plus the thickness of said diaphragm, and a convex portion ateach side of said central portion gradually merging into said levelupper surface of said lower housing portion, whereby when said driveshaft rotates in one direction, said medium enters within that portionof said annular channel which is formed between said partition and thespherical element adjacent thereto in the driving direction, and, as therotation continues is moved into that portion of said annular channelwhich is formed between said element and the next rearwardly adjacentelement, whereupon said medium contained in said chamber is moved in arotary motion toward said outlet, while simultaneously the nextrearwardly adjacent chamber picks up a charge of medium from said inletand then proceeds in the same manner toward said outlet.

4. An apparatus for conveying a gaseous or liquid medium comprising ahousing, a central shaft rotatable within said housing, said housinghaving therein a lower portion with an upper, substantially levelsurface extending at a right angle to said shaft, an annular groovewithin said upper surface coaxially with said shaft, a resilientdiaphragm on said surface and overlying said groove, said groove anddiaphragm together forming an annular channel, an inlet and an outletfor said medium substantially adjacent each other in said housing andcommunicating with said channel in such a manner that communicationbetween said inlet and said outlet is established through said groove byway of a long arcuate chamber as well as by way of a short arcuatechamber, a partition within said short arcuate chamber of said grooveand forming an integral part of said diaphragm so as to close ofl thecommunication between said inlet and outlet by way of said short arcuatechamber of said groove, a plurality of spherical elements in directcontact with the upper surface of said diaphragm, means for guiding saidelements in a fixed spaced relation to each other and so as to rollalong a circular path coinciding with a vertical cylindrical planepassing through the center of said annular groove, as seen in a crosssection thereof, at least one roller intermediate adjacent sphericalelements, means for guiding said rollers in a fixed spaced relation tosaid spherical elements and so as to roll along the upper surface ofsaid diaphragm, and resilient means in frictional contact with saidspherical elements, said last means comprising an annular disk, saiddisk being positively connected with said shaft so as to rotatetherewith, but adapted to slide in axial direction of said shaft, and aspring mounted on said drive shaft so as to rotate therewith and actingupon said disk to press the same resiliently upon said sphericalelements, and thus said elements upon said diaphragm, and said diaphragminto said groove so as to close said groove entirely at such points,said groove when seen in cross section having a central concave portionin the shape of an arc of a circle having a diameter substantially equalto the diameter of said spherical elements plus the thickness of saiddiaphragm, and a-convex portion at each side of said central portiongradually merging into said level upper surface of said lower housingportion, said diaphragm having a depression in its upper surfacesubstantially at a point above said partition and of a dimension andcurvature substantially equal to the impression made in the uppersurface of said diaphragm by said spherical elements, said depression inthe direction of said circular path of said spherical elements graduallymerging into said level upper surface of said diaphragm, whereby whensaid drive shaft rotates in one direction, said medium enters into thatportion of said annular channel which is formed between said partitionand the spherical element adjacent thereto in the driving direction,and, as the rotation continues, is moved into that portion of saidannular channel which is formed between said element and the nextrearwardly adjacent element, whereupon said medium contained in saidchamber is moved in a rotary motion toward said outlet, whilesimultaneously the next rearwardly adjacent chamber picks up a charge ofmedium from said inlet and then proceeds in the same manner toward saidoutlet.

5. An apparatus for conveying a gaseous or liquid medium comprising ahousing, a central shaft rotatable within said housing, said housinghaving therein a lower portion with an upper substantially level surfaceextending at a right angle to said shaft, an annular groove within saidupper surface coaxially with said shaft, a resilient diaphragm on saidsurface and overlying said groove, said groove and diaphragm togetherforming an annular channel, an inlet and an outlet for said mediumsubstantially adjacent each other in said housing and communicating withsaid channel in such a manner that communication between said inlet andsaid outlet is established through said groove by way of a long arcuatechamber as well as by way of a short arcuate chamber, a partition withinsaid short arcuate chamber of said groove and forming an integral partof said diaphragm so as to close off the communication between saidinlet and outlet by way of said short arcuate chamber of said groove, aplurality of spherical elements in direct contact with the upper surfaceof said diaphragm, means for guiding said elements in a fixed spacedrelation to each other and so as to roll along a circular pathcoinciding with a vertical cylindrical plane passing through the centerof said annular groove, as seen in a cross section thereof, a pluralityof tapered truncated rollers so arranged that at least one taperedtruncated roller is intermediate adjacent spherical elements, the axesof said rollers passing through the axis of said drive shaft, means forguiding said rollers in a fixed spaced relation to said sphericalelement and so as to roll along the upper surface of said diaphragm, andresilient means in frictional contact with said spherical elements, saidlast means comprising an annular disk, said disk being positivelyconnected with said shaft so as to rotate therewith, but

spring mounted on said drive shaft so as to rotate therewith and actingupon said disk to press the same resiliently upon said sphericalelements and thus said elements upon said diaphragm, and said diaphragminto said groove so as to close said groove entirely at such points,said groove when seen in cross section having a central concave portionin the shape of an arc of a circle having a diameter substantially equalto the diameter of said spherical elements plus the thickness of saiddiaphragm, and a convex portion at each side of said central portiongradually merging into said level upper surface of said lower housingportion, said diaphragm having a depression in its upper surfacesubstantially at a point above said partition and of a dimension andcurvature substantially equal to the impression made in the uppersurface of said diaphragm by said spherical elements, said depression inthe direction of said circular path of said spherical elements graduallymerging into said level upper surface of said diaphragm, whereby whensaid drive shaft rotates in one direction, said medium enters into thatportion of said annular channel which is formed between said partitionand the spherical element adjacent thereto in the driving direction,and, as the rotation continues, is moved into that portion of saidannular channel which is formed between said element and the nextrearwardly adjacent element, whereupon said medium contained in saidchamber is moved in a rotary motion toward said outlet, 'whilesimultaneously the next rearwardly adjacent chamber picks up a charge ofmedium from said inlet and then proceeds in the same manner toward saidoutlet.

6. An apparatus for conveying a gaseous or liquid medium comprising ahousing, a central shaft rotatable within said housing, said housinghaving therein'a lower portion with an upper, substantially levelsurface extending at a right angle to said shaft, an annular groovewithin said upper surface coaxially with said shaft, a resilientdiaphragm on said surface and superposed upon said groove, said grooveand diaphragm together forming an annular channel, an inlet and anoutlet for said medium substantially adjacent each other in said housingand communicating with said channel in such a manner that communicationbetween said inlet and said outlet is established through said groove byway of a long arcuate chamber as well as by Way of a short arcuatechamber, a partition Within said short arcuate chamber of said grooveand forming an integral part of said diaphragm so as to close off thecommunication between said inlet and outlet by way of said short arcuatechamber of said groove, a plurality of spherical elements in directcontact with the upper surface of said diaphragm, a plurality of taperedtruncated rollers so arranged that at least one tapered truncated rolleris intermediate adjacent spherical elements, the axes of said rollerspassing through the axis of said drive shaft, common means for guidingsaid spherical elements and said rollers in a fixed spaced relation toeach other and so as to roll on the upper surface of said diaphragmalong a circular path, the center of which coincides with a verticalcylindrical plane passing through the center of said annular groove, abell-shaped member secured to said drive shaft, the lower end of saidbellshaped member substantially in sliding contact with said rollers forretaining the same in position in an upward direction, and resilientmeans in frictional contact with said diaphragm, said last meanscomprising an annular disk in contact with said spherical elements, saiddisk being positively connected with said bell-shaped member so as torotate therewith, but adapted to slide in axial direction of said shaftwithin said bell-shaped member, and a spring mounted within saidbell-shaped member and acting upon said disk to press the sameresiliently upon said spherical elements and thus said elements uponsaid diaphragm, and said diaphragm into said groove so as to close saidgroove entirely at such points, said groove when seen in cross sectionhaving a central concave portion in the shape of an arc of a circlehaving a diameter substantially equal to the diameter of said sphericalele ments plus thethickness of said diaphragm, and a convex portion ateach side of said central portion gradually merging into said levelupper surface of said lower housing portion, said diaphragm having adepression in its upper surface substantially at a point above saidpartition and of a dimension and curvature substantially equal to theimpression made in the upper surface of said diaphragm by said sphericalelements, said' depression in the direction of said circular path ofsaid spherical elements gradually merging into said level upper surfaceof said diaphragm, whereby when said drive shaft rotates in onedirection, said medium enters into that portion of said annular channelwhich is formed between said partition and the spherical elementadjacent thereto in the driving direction, and, as the rotationcontinues, is moved into that portion of said annular channel which isformed between said element and the next rearwardly adjacent element,whereupon said medium contained in said chamber is moved in a rotarymotion toward said outlet, while simultaneously the next rearwardlyadjacent chamber picks up a charge of medium fro-m said inlet and thenproceeds in the same manner toward said outlet.

7. An apparatus for conveying a gaseous or liquid medium comprising ahousing, a central shaft rotatable within said housing, said housinghaving therein a lower portion with an upper, substantially levelsurface extending at a right angle to said shaft, an annular groovewithin said upper surface coaxially with said shaft, a resilientdiaphragm on said surface and superposed upon said groove, said grooveand diaphragm together forming an annular channel, an inlet and anoutlet for said medium substantially adjacent each other in said housingand communicating with said channel in such a manner that communicationbetween said inlet and said outlet is established through said groove byway of a long arcuate chamber as well as by Way of a short arcuatechamber, a partition within said short arcuate chamber of said grooveand forming an integral part of said diaphragm so as to close off thecommunication between said inlet and outlet by way of said short arcuatechamber of said groove, a plurality of spherical elements in directcontact with the upper surface of said diaphragm, a plurality of taperedtruncated rollers so arranged that at least one tapered truncated rolleris intermediate adjacent spherical elements, the axes of said rollerspassing through the axis of said drive shaft, each of said taperedrollers having a substantially elliptical central projection thediameter of which is smaller than the diameter of said sphericalelements, common means for guiding said spherical elements and saidrollers in a fixed spaced relation to each other and so as to roll onthe upper surface of said diaphragm along a circular path, the center ofwhich coincides with a vertical cylindrical plane passing through thecenter of said annular groove, a bellshaped member secured to said driveshaft, the lower end of said bell-shaped member substantially in slidingcontact with said rollers for retaining the same in position in anupward direction, and resilient means in frictional contact with saiddiaphragm, said last means comprising an annular disk in contact withsaid spherical elements, said disk being positively connected with saidbell-shaped member so as to rotate therewith, but adapted to slide inaxial direction of said shaft within said bellshaped member, and aspring mounted within said bellshaped member and acting upon said diskto press the same resiliently upon said spherical elements and thus saidelements upon said diaphragm, and said diaphragm into said groove so asto close said groove entirely at such points, said groove when seen incross section having a central concave portion in the shape of an arc ofa circle having a diameter substantially equal to the diameter of saidspherical elements plus the thickness of said diaphragm, and a convexportion at each side of said central portion gradually merging into saidlevel upper surface of said lower housing portion, said diaphragm havinga depression in its upper surface substantially at a point above saidpartition and of a dimension and curvature substantially equal to theimpression made in the upper surface of said diaphragm by said sphericalelements, said depression in the direction of said circular path of saidspherical elements gradually merging into said level upper surface ofsaid diaphragm, whereby when said drive shaft rotates into onedirection, said medium enters into that portion of said annular channelwhich is formed between said partition and the spherical elementadjacent thereto in the driving direction, and, as the rotationcontinues, is moved into that portion of said annular channel which isformed between said element and the next rearwardly adjacent element,whereupon said medium contained in said chamber is moved in a rotarymotion toward said outlet, while simultaneously the next rearwardlyadjacent chamber picks up a charge of medium from said inlet and thenproceeds in the same manner toward said outlet.

8. An apparatus as. defined in claim 6, wherein said tapered rollerseach have a central portion of substantially elliptical cross sectionalconfiguration, the radius of the generatrix of said central portionbeing larger than half the maximum diameter of said central portion.

9. An apparatus as defined in claim 3, wherein said guiding meanscomprise a cage for holding said spherical elements in a fixed spacedrelation to each other, said cage having outwardly directed recessesadapted to receive said elements therewithin.

10. An apparatus as defined in claim 3 wherein said guiding meanscomprise a cage for holding said spherical elements in a fixed spacedrelation to each other, said cage having outwardly directed recessesadapted to receive said elements therewithin, and a ring surroundingsaid cage, said sperical elements having a pointlike contact with theinner edge of said ring.

11. An apparatus as defined in claim 3, wherein said guiding meanscomprise a platelike cage for holding said spherical elements in a fixedspaced relation to each other and completely enclosing said elementswithin the plane of said cage.

12. An apparatus as defined in claim 3, wherein said guiding meanscomprise a cage for holding said spherical elements in a fixed spacedrelation to each other, said cage having inwardly directed recessesadapted to receive said elements therewithin.

13. An apparatus as defined in claim 3, wherein the surface of said diskin contact with said spherical elements consists of a material similarto that of said diaphragms.

14. An apparatus as defined in claim 1 wherein said diaphragm haselastic inserts for reinforcing the same.

15. An apparatus as defined in claim 2, wherein said groove has a narrowslot in its wall on each side of the inlet and outlet thereof andextending in the direction of said circular path for preventing thespherical element when rolling over said inlet and outlet of saidgroove, respectively, from closing the same completely.

16. An apparatus as defined in claim 1, wherein said partition comprisesmeans for drawing said diaphragm at least at one point into said grooveand for securing it tightly to the wall thereof.

References Cited in the file of this patent UNITED STATES PATENTS 34,190Baldwin Jan. 21, 1862 612,834 Dieckmann Oct. 25, 1898 922,205 Still May18, 1909 2,671,412' Rand Mar. 9, 1954

